Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 325/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 29.52 (749.7) | 1.28 (32.5) 4.5% |
| Width inches (mm) | 12.8 (325) | 12.8 (325) | 0 (0) 0% |
| Circum. inches (mm) | 88.71 (2253.15) | 92.73 (2355.25) | 4.02 (102.1) 4.5% |
| Sidewall Height inches (mm) | 5.12 (130) | 5.76 (146.25) | 0.64 (16.25) 12.5% |
| Revolutions per mile (km) | 714.26 (443.82) | 683.3 (424.58) | -30.96 (-19.24) -4.3% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.91 mph (33.65 km/h) |
| 25 mph (40.23 km/h) | 26.13 mph (42.06 km/h) |
| 30 mph (48.28 km/h) | 31.36 mph (50.47 km/h) |
| 35 mph (56.33 km/h) | 36.59 mph (58.88 km/h) |
| 40 mph (64.37 km/h) | 41.81 mph (67.29 km/h) |
| 45 mph (72.42 km/h) | 47.04 mph (75.7 km/h) |
| 50 mph (80.47 km/h) | 52.27 mph (84.11 km/h) |
| 55 mph (88.51 km/h) | 57.49 mph (92.53 km/h) |
| 60 mph (96.56 km/h) | 62.72 mph (100.94 km/h) |
| 65 mph (104.61 km/h) | 67.95 mph (109.35 km/h) |
| 70 mph (112.65 km/h) | 73.17 mph (117.76 km/h) |
| 75 mph (120.7 km/h) | 78.4 mph (126.17 km/h) |
| 80 mph (128.75 km/h) | 83.63 mph (134.58 km/h) |
| 85 mph (136.79 km/h) | 88.85 mph (142.99 km/h) |
| 90 mph (144.84 km/h) | 94.08 mph (151.4 km/h) |
| 95 mph (152.89 km/h) | 99.3 mph (159.82 km/h) |
| 100 mph (160.93 km/h) | 104.53 mph (168.23 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1739 | 2020 | 2175 | 2272 | 2375 | 2449 | 2531 | 2627 | 2760 | 2893 | 3041 | 3160 | 3374 | 3611 | 3796 | 3914 | 3981 | 4225 | 4565 | 5305 |
Better Fuel Economy Factory Ratios Increased Power
